A. "This would involve conflicts with several European countries- Britain, France, Spain, etc. Do you think the Confederates would be prepared for more war?"
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No, I didn't conceive of global expansion immediately, but as a gradual process. First recover from the war; perhaps, disarm the federal armies; build up military power; enjoy the fruits of slavery; ruin the land -- then, get more; acquire more land (maybe from weaker states) by intimidation or aggression. (Who's going to interfere?)
Repeat the above cycle with each nation conquered -- one at a time -- and in a couple of decades, we have a growing Slave empire. Strong enough to resist European objections (even if they formed an alliance).
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B. "The reason the South wanted slavery in the territories was political. Territories become states. States send representatives to Congress. In other words- to maintain a balance in the US Congress. But if the South had gained its independence...there would be no need to maintain a balance in the US Congress. They wouldn't be there."
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The reason was economic, then political. You forget that the reason the slavers even had power in Congress was when they represented slave states. That's what the Missouri Compromise was all about. Adopt a new slave State and tip the balance of power. Acquire new slave states, further politically weakening the North, and there will be strong objections.
Slavery degrades free labor.
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C. "The North wanted the territories reserved for free white people. No blacks allowed- slave or free. And everyone knows what happened to the native population. "
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What the North wanted for the black versus white people is not one solid opinion-block. So you can't possibly say WHAT the North wanted (sorry).
There was a range opinions -- which had to be worked out -- that's what time and the democratic process is about. Time and means for people to become better acquainted with their new fellow citizens -- and how to best interrelate with them.
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